What does this app actually do? In fact this apps saves your $99 (USD) and allows you to run those apps which you have created or other developers’ apps without having the Marketplace registration account.
Step 1: Downlaod and install Windows Phone 7 SDK.
Alternatively you can also try by installing the registry key only. But its better to install the WP 7 SDK if you don’t want to get any connection errors. After installing Registry Key or SDK, restart your PC.
Step 2: After reboot make it sure that you have the correct key there. Open the RUN box and type regedit to go to registry editor.
Step 3: Now connect the WP 7 with PC via USB cable.
Step 4: Run the Zune. Please ensure your device has a “full sync” relationship with the Zune client, not a “guest” relationship.
Step 5: Download and open ChevronWP7.exe file and run it.
Step 6: Follow the ChevronWP on-screen instructions to unlock the device.